Ch. 6, 7  atomic structure, light, & periodic trends        80 points (2 ec)                                    AP chemistry

In problems involving any calculation, show your work in an organized manner, include (i) any relevant equation (or formula), (ii) conversion factor(s), (iii) put the proper units in your calculations and answer, and (iv) have the proper number of significant figures in your answer.

 1. Sketch the atomic orbital (AO) with respect to the x-, y-, or z- axis (& label it), as needed to observe its relative position to these axis.  [10 points]

a. 2 s and 3 s AO; label AO

b. dxz

c. px & pz; label AO

2.  In regards to Arsenic,  [10 points]

a. What is the orbital diagram for arsenic ?

b. Identify the valence and core electrons

3. In the hydrogen atom, the electron energy level is

En = - 2.18 * 10-18 J   

and an electron goes from the n = 3 to n = 5 electron energy level.  [12 points]

a. Did the atom absorb or emit light ?

b. What is the energy of the absorbed or emitted light ?

c. What is the corresponding wavelength (in m) of the light that was emitted or absorbed ?

4.  Describe how an atom’s orbital diagram predicts if an atom can act like a magnet ?  [5 poitns]

5. What is the relative atomic size of __;  rationale / basis of your answer.  [10 points]

a. Magnesium versus calcium

b. Sodium versus magnesium

6. What is the relative 1st ionization energy of ___; rationale / basis of your answer.  [10 points]

a. Carbon versus nitrogen

b. Nitrogen versus oxygen

7.  Based on the following hypothetical data

[chemical] (mM)

Intensity of light (photons / sec)

Blank

670

25

385

50

222

75

135

100

73

unknown

175

estimate the concentration of the unknown sample using a graph; label both axis.  The intensity of light is after the light passed thru the sample.  [10 points]

8. Old topic:  organic chemistry  [15 points]

a. Sketch a ketone with methyl group(s)

b. Sketch an ether with propyl group(s)

c. Sketch a carboxylic acid with an ethyl group(s)